Examples of those devices that adhere to the surface of an object, when negative pressure is formed internally, and move along the surface include the one described below:
A device capable of adhering to and moving along various inclined or substantially vertical surfaces of ships, buildings, etc. was disclosed in Japan Patent Application Examined Publication No. 60-26752 (U.S. Pat. No. 4,095,378 Claims and Drawings).
The Device comprises the main casing, a plurality of wheels secured to the main casing as a means for mobility, a sealing member connected to the main casing having a free end which is caused to contact the surface of an object, and a negative pressure forming means to discharge externally the liquid contained in an area defined by the main casing, the surface and the sealing member, the pressure of which is to be reduced. In such a device, the energization of the negative pressure forming means causes the liquid inside the said area to be discharged externally, and the pressure of the liquid that acts on the main casing because of the liquid pressure difference between the inside and the outside of the said area is transmitted to the surface of an object via the wheels, such liquid pressure allowing the Device to adhere to the surface. Additionally, the rotation of the wheels by way of a driving means, such as an electric motor, during such adhesion state allows the Device to move along the surface by the action of the wheels. Further, such a device has a remote-controlled working device, such as a means for blasting a cleaning and polishing material against the surface inside the said area, mounted thereon, allowing various operations on the surface of an object in a safe and efficient manner.
Examples of those devices that adhere to the surface of an object immersed in liquid, move along the surface and act on the surface include the one which is described below and is disclosed in Japan Patent Application Unexamined Publication No. 2003-285782:
Such a device is equipped with two areas filled with gas that enable the surface of the object to be in contact with gas only, and is equipped with a device that acts on the surface of the object.
This invention comprises a device capable of adhering to and moving along the surface of an object immersed in liquid, comprising the main casing at least comprising an outer casing and an inner casing, an outer sealing member mounted at the opening of the outer casing, part of which is caused to contact the surface of the object, an inner sealing member mounted at the opening of the inner casing, part of which is caused to contact the surface of the object, and a means for moving along the surface of the object while maintaining the distance between the main casing and the surface of the object at a certain distance, wherein at least the outer casing, the outer sealing member and the inner sealing member, together with the surface of the object, define Area I, and at least the inner casing and the inner sealing member, together with the surface of the object, define Area II.
Examples of those devices that adhere to the surface of an object surrounded with gas move along the surface and act on the surface include the one which is described below and is disclosed in Japan Patent Application Unexamined Publication No. 2004-151012:
This invention provides a device capable of covering the surface of an object situated in gas with a region filled with liquid and of moving such region, capable of sucking and collecting such liquid from the surface of the object wetted by the liquid and of drying such surface, and is capable of allowing such region to adhere to and crawl along the surface of the subject, while conducting ultrasonic flaw detection or ultrasonic cleaning of the surface of the object.
This invention provides a device comprising a stereoshaped first region having an annular surface A and a stereoshaped second region having an annular surface B wherein the surface A is the boundary surface between the surface of an object and Area I and the surface B is the boundary surface between the surface of an object and Area II, the portion defining the outer boundary of the surface A is provided with an outer seal member, the portion defining the inner boundary of the surface A is provided with an inner seal member, Area I is connected to a gas suction means, Area II is connected to a liquid supply means, Area I is located on the downstream side of gas surrounding the Device, Area I is located on the downstream side of Area II, and the liquid flowing out of Area II reaches Area I and is subsequently transported by suction to the suction means.
[Patent Reference 1]
    Japan Patent Application Examined Publication No. 60-26752[Patent Reference 2]    Japan Patent Application Unexamined Publication No. 2003-285782[Patent Reference 3]    Japan Patent Application Unexamined Publication No. 2004-151012
In order to use the Device concerned to Japan Patent Application Examined Publication No. 60-26752 below the surface of a liquid, there are following problems to be solved.
The first problem is that, when a cleaning and polishing material is blasted onto the surface of an object immersed in liquid using compressed air, for example, to roughen the surface, upon which time, the used cleaning and polishing material is to be recovered and collected in a container located on land using air suction, the surrounding liquid must be disallowed to enter the blasting area of the cleaning and polishing material. There are various other operations that must also disallow the entry of liquid into the area of the surface of an object being worked on, similar to the case of the blasting operation of a cleaning and polishing material. For example, those operations that utilize a thermal spraying device, a welding device which adheres molten materials to surfaces, a device which adheres plastic sheets to surfaces, a device which sprays paint or glue onto surfaces, and a device which heat-processes surfaces are affected adversely by the entry of liquid into the area of the surface of an object being worked on. These devices exhibit better performance when the surface of the object being worked on is in contact with gas than when it is in contact with liquid.
A device that works on the surface of an object immersed in liquid whose performance is adversely affected by the entry of the liquid into the area of the surface of the object being worked on, as described above, needs to have an area free from the entry of liquid and filled with gas.
The second problem is that, when the Device immersed in liquid has an area filled with gas, the pressure of the area filled with gas needs to be controlled so that the difference between the pressure of the area filled with gas and the pressure of the liquid is kept constant as the liquid pressure may increase because it increases as the depth increases. If the liquid pressure is much greater than the pressure of the area filled with gas, the pressure of the liquid presses the area filled with gas against the surface of the object with great force, and the Device will need extremely strong power to move along the surface.
The third problem is that, when compressed gas is jetted into the area filled with said gas, as in the case of the blasting operation of a cleaning and polishing material, the compressed air pressure needs to be controlled so that the difference between the pressure of the area filled with said gas and the pressure of the compressed gas is kept constant. If the difference between the pressure of the area filled with said gas and the pressure of the compressed gas decreases, the flow of the compressed gas will decrease, and the work being performed on the surface of an object using the compressed gas will suffer imperfection.
There exists the problem to be solved as described below when the Device disclosed in Japan Patent Application Unexamined Publication No. 2003-285782 is used below the surface of the water:
That is to say, being the pressure of gas inside of Area I at a higher level than the pressure of liquid surrounds the Device, some gas inside of Area I is issued to outside of the Device through the gap between the outer sealing membrane and the surface of an object. Therefore, it is caused the pollution of the water by the Device when gas from Area I includes poisonous material such as degraded paint particle which includes heavy metal such as lead.
There exists the problem to be solved as described below when the Device disclosed in Japan Patent Application Unexamined Publication No. 2004-151012 is applied in gas:
That is to say, being filled the Area II with liquid, it is impossible for a thermal spraying device which acts on the surface of an object to be equipped with Area II. Further, being filled the Area II with liquid, it is impossible for Area II to be equipped with the Devices that allow molten materials to adhere to a surface such as welding devices, devices that allow plastic sheets to adhere to a surface, devices that spray paint or glue onto a surface, devices that heat-process the surface of an object, and various other devices.
If Area II is filled with an inert gas, it is exhibited the excellent performance for the Devices described above which are equipped with Area II because the surface inside of Area II is in contact with an inert gas.
However, it is impossible for the Devices described above to be equipped with Area II of the Device disclosed in Japan Patent Application Unexamined Publication No. 2004-151012 because Area II of the Device of the patent is filled with liquid.
Accordingly, technical objectives of the present invention are as follows:
Regarding to the first problem of the Device concerned to Japan Patent Application Examined Publication No. 60-26752, the first technical objective of the present invention is to provide a device capable of adhering to the surface of an object immersed in liquid and moving along the surface that has an area filled with gas.
Regarding to the second and the third problems of the Device concerned to Japan Patent Application Examined Publication No. 60-26752, the second and the third technical objectives and the means to solve the objectives of the present invention have been disclosed in Japan Patent Application Unexamined Publication No. 2003-285782. So description is omitted.
Regarding to the problem of the Device concerned to Japan Patent Application Unexamined Publication No. 2003-285782, the technical objective of the present invention is to provide a device capable of adhering to and moving along the surface of an object immersed in liquid, wherein the pressure of gas in Area I is so maintained at a lower level than the pressure of the liquid surrounding the Device that gas inside of Area I may not be issued outside of the Device from the gap between the outer sealing member and the surface of the object.
Regarding to the problem of the Device concerned to Japan Patent Application Unexamined Publication No. 2004-151012, the technical objective of the present invention is to provide a device capable of adhering to and moving along the surface of an object in the air, wherein the Device is so equipped with the area II which is filled with gas that the various kinds of tools which works on the surface of the object may be installed in the area II such as a thermal spraying device, a welding device which adheres molten materials to surfaces, a device which adheres plastic sheets to surfaces, a device which sprays paint or glue onto surfaces, and a device which heat-processes surfaces.
Described above were problems associated with prior art and technical objectives intended to be solved by the present invention of a device capable of adhering to and moving along the surface of an object.